Photoselective Shade Nets Research Articles

Photo Selective Shade Net: An Effective Tool to Reduce the Impact of Global Warming and Pesticide Residues in Vegetable Production: A Review

Photo selective shade net is a product made of plastic fibers connected together with each other, forming a regular porous structure and allowing gases, liquid and light to pass through. It has a capacity to selectively filter the intercepted solar radiation, in addition to their protective function. Vegetables are considered as protective food which are highly perishable in nature. High temperature due to global warming, climate change and excessive use of chemicals are some of the burning issues of vegetable production. Photo selective shade net can be a partial solution for these problems. Vegetable crops grown under different photo selective shade net shows productive responses thus by application of various Photo selective shade nets we can improve the quality as well as production of vegetable crops.

Pigments in flower stems of lisianthus under different photoselective shade nets

Abstract The lisianthus culture is demanded to produce cut flowers and pot vases, grown in a greenhouse using advanced techniques. The present study aimed to evaluate the pigments of different lisianthus cultivars in different photoselective shade nets. The cultivars Flare Deep Rose (pink), Echo Blue BL (purple) and Allemande White BI (white) were cultivated under light-diffusing polyethylene film cover and blue and red color photoselective nets with a shading capacity of 30%, in addition to the control treatment, without the use of the net. The results showed higher values of chlorophyll b and total in the red photoselective net, independent of the cultivar. Leaf colorimetry showed the most intense shade of green was from the cultivar Echo Blue BL. On the other hand, the control showed more intensity, with no significant difference in the leaf green intensity on the blue and red shade nets. In the petals, the cultivar Echo Blue BL showed a more intense blue shade in the red net, however low grade of anthocyanin than in the blue one. In the anthocyanin pigment, this cultivar had lower levels in the treatment of the red net. The results indicate that the use of photoselective shade nets in the culture of lisianthus changes the content of the pigments studied, in varying intensity, depending on the cultivar.

Effect of Photo-Selective Shade Nets on Pollination Process and Nut Development of Corylus avellana L.

Hazelnut (Corylus avellana L.) is one of the most appreciated nut crops, which is motivating the cultivation outside its historical production areas. Despite that, there is still limited knowledge about the floral biology of the species and its developmental fruiting stages under different environments. Adverse climatic conditions can threaten the pollination process and fruit development. In South Africa, the deciduous fruit industry identified the net shading as a tool to mitigate the effects of unfavorable abiotic events. The objective of this work was to investigate the effects of photo-selective nets on the pollination process and nut development of C. avellana. Mature hazelnut trees were maintained under netting and compared with the ones in open field. Microscopic examination of female flower and developing nuts were conducted in order to observe the pollen tube growth and the pattern of disodium fluorescein transport into the funiculus and ovule. The results showed differences in pollen tubes growth and timing between the treatments. Generally, trees under nets showed higher rate in pollen tubes developing and reaching the base of the style. On the contrary, the tests carried out in open field showed a higher ratio of pollen tubes arrested in the style. The results also indicated differences in ovules abortion. Developing fruits that showed an interruption point at the funicle level or at junction point of the ovule were classified as aborting fruits (blank nuts at harvest time). A higher rate of abortion was detected in open field compared to the plants under netting. In conclusion, the shade nets influenced the pollen tube growth and the nut development, principally due to micro-climate modification. Therefore, further investigations are needed to analyze the influence of light spectra and to determine the sustainability of photo-selective nets over several years.

Influence of photoselective shade nets on growth and yield of Asparagus

Study on “Influence of photoselective shade nets on growth and yield of Asparagus” was carried out at KRC college of Horticulture, Arabhavi, Gokak, Karnataka during 2018-19. The result revealed that, among photoselective shade nets, plant height, plant spread and internodal length were higher under red shade net. Plants grown under grey shade net recorded higher number of cut cladophylls per plant (54.89) and per square meter (406.73). Cladophylls harvested from grey shade net recorded maximum vase life (12 days) followed by red (10.28 days). Among different asparagus species, A. densiflorus ‘Sprengeri’ performed better with respect to vegetative growth and yield. Higher cumulative number of cut cladophylls per plant (61.07) and per square meter (452.50) was recorded in A. densiflorus ‘Sprengeri’ followed by A. densiflorus ‘Myers’. A. densiflorus ‘Myers’ recorded maximum vase life (10.20 days) followed by A. myriocladus (10.10 days).

Preliminary study of the behavior of a courgette crop grown under photoselective shade nets

Preliminary study of the behavior of a courgette crop grown under photoselective shade nets

Photoselective shade nets for pepper cultivation in southeastern Spain

Photoselective shade nets for pepper cultivation in southeastern Spain

Photo-selective shade nets on the production and quality of sugarcane plantlets

ABSTRACT Brazil is the world’s largest producer of sugarcane (Saccharum officinarum L.) and research aimed at propagation has promoted higher quality in production. The objective of this study was to investigate the effect of the variation of micrometeorological elements on the survival and quality of pre-sprouted sugarcane plantlets. The study was carried out in a protected environment (UFRPE). Plantlets of the cultivar RB92579 were obtained by the technique of production of pre-sprouted plantlets. The protected environments were divided into four modules covered with low-density polyethylene plastic + photo-selective shade nets and one module without shade net. Micrometeorological data of global and photosynthetically active solar radiation, air temperature, substrate temperature, relative humidity and the solar radiation spectrum were recorded in each module. The experiment was conducted in a completely randomized design and the principal component analysis was used to verify the association between the cultivation modules, micrometeorological variables and crop variables. Anti-UV low-density polyethylene plastic + freshnet led to lower transmittance of global solar radiation, higher percentage of photosynthetically active radiation and lower plantlet mortality. Substrate temperature above 30.2 °C resulted in higher plantlet mortality. Larger spectrum in the red range led to the production of better quality plantlet. The use of freshnet shade net promoted adequate conditions for the cultivation of sugarcane plantlets and allows obtaining better quality plantlets.

The effect of light variations by photoselective shade nets on pigments, antioxidant capacity, and growth of two ornamental plant species: Marigold (Calendula officinalis L.) and violet (Viola tricolor)

A new group of colored shade net has been developed that can influence the quality and quantity of the light intercepted by the plants. To explore the effect of applying colored shade nets on physi...

Variety-specific responses of lettuce grown under the different-coloured shade nets on phytochemical quality after postharvest storage

ABSTRACTThis study illustrates the effects of light quality as influenced by photo-selective shade nets (red, yellow, and pearl with 40% shade) and the widely used commercial black net (25% shade) on overall retail quality and phytochemical contents of three lettuce (Lactuca sativa L.) varieties (two green varieties, Ashbrook and Aquarell, and a red variety, Exbury) at after postharvest storage. Variety-specific responses were observed with respect to different coloured shade nets with regards to the accumulation of β-carotene, ascorbic acid, flavonoids (kaempferol, isorhamnetin, quercetin, myricetin, anthocyanin), and antioxidant activity at harvest. Growing var. Ashbrook under the pearl net improved the ascorbic acid and myricetin contents after postharvest storage. Var. Exbury (red) produced under the black net showed higher retention of ascorbic acid, and anthocyanin contents after postharvest storage. Also pearl net production improved the β-carotene content after postharvest storage in var. Aquarell. All lettuce types produced under the pearl nets showed less weight loss, and overall acceptance after postharvest storage. Spectral quality under the shade nets enabled us to improve the phytochemical content and antioxidant properties in light-sensitive varieties Ashbrook Aquarell and Exbury, during winter season.

Producción de pepino en ambientes diferenciados por mallas de sombreo fotoselectivo

Cucumber production in several light environments by photoselective shade nets During the agricultural cycles of 2011/2012 and 2012/2013, the transmitted sunlight by six nets with 30% shade: aluminized, gray, pearl, blue, red (colored) and black, and its effects on growth, development and yield of cucumber were evaluated. The red net transmitted 42.6, 23.7, 40.3, 52.9 and 57.3% more total sun radiation (350-1050 nm), photosynthetic active radiation (400 to 700 nm), red light (600-700

Shading stock plants with photoselective nets affects the yield and rooting quality of their cuttings

SummaryReducing light levels, decreasing the red to far-red (R:FR) light ratio, and exposing stock plants to blue light have been shown to increase the rooting potential of cuttings in various species. Here, we tested the effects of growing stock plants under photoselective shade nets, altering the spectrum of transmitted sunlight, and/or enriching the relative level of scattered light, on the yield and rooting quality of cuttings. Three ornamental plants, Pelargonium (including three cultivars, ‘Isabel’, ‘Alara’ and ‘De Capo’), Laurus nobilis, and Heteromelis normally propagated by rooting cuttings, were chosen for this study. The nets chosen were a black neutral net and pearl, blue, or yellow photoselective nets. In Heteromelis, the pearl net caused a significant increase in the number of rooted cuttings per plant, but had no effect on the number of rooted cuttings in Pelargonium or L. nobilis stock plants. Instead, significant increases in cutting yields in all three Pelargonium cultivars and in L. nobilis were observed under the yellow net. The three photoselective nets also differed in their effects on rooting among the different species tested. None of the three photoselective nets decreased the rooting percentage or the frequency of rooting compared to the black net, in any experiment. Both the yellow and blue nets increased the rate at which the Pelargonium cuttings rooted. The yellow shade net had a double effect on all three Pelargonium cultivars, increasing the yield of cuttings per plant and also increasing their rate of rooting. In the two woody species, L. nobilis and Heteromelis, cuttings from stock plants grown under the pearl net rooted more efficiently compared to those from plants grown under the black net. Both the pearl and the blue nets increased the rooting efficiency in Heteromelis.

TREE VIGOR, FRUIT YIELD AND QUALITY OF NECTARINE TREES GROWN UNDER RED PHOTOSELECTIVE ANTI-HAIL NETS IN SOUTHERN ITALY

In Italy, hailstorms represent a major threat for fruit tree cultivation. Therefore many peach growers have protected their orchards with anti-hail nets. Many studies have demonstrated that photoselective shade nets can induce interesting photomorphogenic effects on several cultivated species. The aim of the present research was to study the effect of red photoselective anti-hail nets on nectarine tree vigor, fruit yield, and fruit quality. The study was carried out in a private orchard located in Eboli (Southern Italy) on mature nectarine trees ‘Laura’ grafted on GF677. On February 2008, five rows of trees were covered with a red photoselective anti-hail net (30% shade factor), whereas another five rows were covered with a white, transparent anti-hail net (10% shade factor) that is the most common type of anti-hail net used in the area. During the experiment a number of parameters related to tree vigor, fruit yield and quality were measured. Trees under the red net had higher light interception than trees under the white net and this suggests that the red net induced an increase in tree vigor, as previously reported for other species. Net color did not significantly affect the number of fruit per tree and fruit yield. Similarly, there were no significant differences in fruit size distribution or fresh fruit weight between trees under the two types of nets. Both cover and ground color of fruit skin was slightly, but significantly, less under red nets. On the other hand, fruit of trees under the red net tended to have significantly higher flesh firmness, lower soluble solids content and lower percent dry matter than fruit of trees under the white net. These effects may be related to a slight delay in fruit maturation induced by the red net or to a negative effect of this net on sugar accumulation in the fruit (potentially because of the higher shade factor of the red net compared to the white net).